The invention relates to an engageable and disengageable coupling or clutch for engaging and disengaging a drive between shafts using an intermediate member to interconnect and disconnect co-axial driving and driven shaft elements.
U.S. Pat. No. 3,709,343 (as one example) discloses a toothed or dog clutch of this type, in which two toothed rims are arranged on one side of the clutch for facilitating engagement of the latter, these toothed rims being offset from one another by less than half the tooth pitch. However, this clutch does not provide a very compact assembly and has limitations in the robustness of the connection it provides between the driving and driven shafts.
Thus, there can be problems in providing a clutch which enables very large power units to be coupled and uncoupled, e.g., units providing powers of a greater order of magnitude than 100 MW, and speeds of perhaps 3000 r.p.m., where the clutch is to be capable of connecting together the two shaft ends such that deformations will be precluded in a relatively resilient shaft system. By reason of the high powers and of the relatively high speeds indicated, it is not feasible to use, for example, any types of clutch which comprise eccentric parts. Also, it is not possible to use a clutch of a known type of construction, which has simply been given greater dimensions to enable it to transmit such a power. What is required is a clutch which, in its engaged condition and under load, secures together the shaft ends of for example a generator and turbine as securely as a flanged connection, although providing also the facility of disengagement.